Remove generated directories with 100s of files.

client/dom/generated/src/interface/IDBDatabase.dart

-// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-// WARNING: Do not edit - generated code.
-
-interface IDBDatabase {
-
-  final String name;
-
-  final List<String> objectStoreNames;
-
-  EventListener onabort;
-
-  EventListener onerror;
-
-  EventListener onversionchange;
-
-  final String version;
-
-  void addEventListener(String type, EventListener listener, [bool useCapture]);
-
-  void close();
-
-  IDBObjectStore createObjectStore(String name);
-
-  void deleteObjectStore(String name);
-
-  bool dispatchEvent(Event evt);
-
-  void removeEventListener(String type, EventListener listener, [bool useCapture]);
-
-  IDBVersionChangeRequest setVersion(String version);
-
-  IDBTransaction transaction(var storeName_OR_storeNames, [int mode]);
-}